Along with development of a communication technology, functions of a terminal become increasingly diversified and complicated, and more and more components are required to be mounted in a terminal body, so that a clearance area in the terminal body for designing of an antenna becomes increasingly small. Therefore, in many terminals, an antenna is replaced with a metal frame on a terminal casing to reduce occupation of the clearance area.
In a related technology, replacing a single antenna with a metal frame in a limited clearance area may meet requirements of a second-generation mobile communication technology and a third-generation mobile communication technology. However, for inter-band carrier aggregation in a carrier aggregation technology introduced into a Long Term Evolution Advanced (LTE-A) specification, since aggregated carriers are located in different working frequency bands, terminal antennae are required to be divided into a low and intermediate-frequency antenna and a high-frequency antenna when the terminal antennae are designed. Therefore, how to implement two antennae in a limited clearance area and ensure high isolation between the antennae under the condition of replacing an antenna with a metal frame is a problem urgent to be solved.